# overrideable build dir, default is in-place
BUILDDIR ?= .
# overridable target/src/tools/flags/etc
ifneq ($(wildcard test.c main.c),)
TARGET ?= $(BUILDDIR)/lfs
else
TARGET ?= $(BUILDDIR)/liblfs.a
endif


CC       ?= gcc
AR       ?= ar
SIZE     ?= size
CTAGS    ?= ctags
NM       ?= nm
OBJDUMP  ?= objdump
VALGRIND ?= valgrind
GDB		 ?= gdb
PERF	 ?= perf

# guess clang or gcc (clang sometimes masquerades as gcc because of
# course it does)
ifneq ($(shell $(CC) --version | grep clang),)
NO_GCC = 1
endif

SRC  ?= $(filter-out $(wildcard *.t.* *.b.*),$(wildcard *.c))
OBJ  := $(SRC:%.c=$(BUILDDIR)/%.o)
DEP  := $(SRC:%.c=$(BUILDDIR)/%.d)
ASM  := $(SRC:%.c=$(BUILDDIR)/%.s)
CI   := $(SRC:%.c=$(BUILDDIR)/%.ci)
GCDA := $(SRC:%.c=$(BUILDDIR)/%.t.gcda)

TESTS ?= $(wildcard tests/*.toml)
TEST_SRC ?= $(SRC) \
		$(filter-out $(wildcard bd/*.t.* bd/*.b.*),$(wildcard bd/*.c)) \
		runners/test_runner.c
TEST_RUNNER ?= $(BUILDDIR)/runners/test_runner
TEST_A     := $(TESTS:%.toml=$(BUILDDIR)/%.t.a.c) \
		$(TEST_SRC:%.c=$(BUILDDIR)/%.t.a.c)
TEST_C     := $(TEST_A:%.t.a.c=%.t.c)
TEST_OBJ   := $(TEST_C:%.t.c=%.t.o)
TEST_DEP   := $(TEST_C:%.t.c=%.t.d)
TEST_CI	   := $(TEST_C:%.t.c=%.t.ci)
TEST_GCNO  := $(TEST_C:%.t.c=%.t.gcno)
TEST_GCDA  := $(TEST_C:%.t.c=%.t.gcda)
TEST_PERF  := $(TEST_RUNNER:%=%.perf)
TEST_TRACE := $(TEST_RUNNER:%=%.trace)
TEST_CSV   := $(TEST_RUNNER:%=%.csv)

BENCHES ?= $(wildcard benches/*.toml)
BENCH_SRC ?= $(SRC) \
		$(filter-out $(wildcard bd/*.t.* bd/*.b.*),$(wildcard bd/*.c)) \
		runners/bench_runner.c
BENCH_RUNNER ?= $(BUILDDIR)/runners/bench_runner
BENCH_A     := $(BENCHES:%.toml=$(BUILDDIR)/%.b.a.c) \
		$(BENCH_SRC:%.c=$(BUILDDIR)/%.b.a.c)
BENCH_C     := $(BENCH_A:%.b.a.c=%.b.c)
BENCH_OBJ   := $(BENCH_C:%.b.c=%.b.o)
BENCH_DEP   := $(BENCH_C:%.b.c=%.b.d)
BENCH_CI    := $(BENCH_C:%.b.c=%.b.ci)
BENCH_GCNO  := $(BENCH_C:%.b.c=%.b.gcno)
BENCH_GCDA  := $(BENCH_C:%.b.c=%.b.gcda)
BENCH_PERF  := $(BENCH_RUNNER:%=%.perf)
BENCH_TRACE := $(BENCH_RUNNER:%=%.trace)
BENCH_CSV   := $(BENCH_RUNNER:%=%.csv)

CFLAGS += -g3
CFLAGS += -I.
CFLAGS += -std=c99 -Wall -Wextra -pedantic
CFLAGS += -Wmissing-prototypes
ifndef NO_GCC
CFLAGS += -fcallgraph-info=su
CFLAGS += -ftrack-macro-expansion=0
endif

ifdef DEBUG
CFLAGS += -O0
else
CFLAGS += -Os
endif
ifdef TRACE
CFLAGS += -DLFS_YES_TRACE
endif
ifdef YES_COV
CFLAGS += --coverage
endif
ifdef YES_PERF
CFLAGS += -fno-omit-frame-pointer
endif
ifdef YES_PERFBD
CFLAGS += -fno-omit-frame-pointer
endif

ifdef VERBOSE
CODEFLAGS    += -v
DATAFLAGS    += -v
STACKFLAGS   += -v
STRUCTSFLAGS += -v
COVFLAGS     += -v
PERFFLAGS    += -v
PERFBDFLAGS  += -v
endif
# forward -j flag
PERFFLAGS   += $(filter -j%,$(MAKEFLAGS))
PERFBDFLAGS += $(filter -j%,$(MAKEFLAGS))
ifneq ($(NM),nm)
CODEFLAGS += --nm-path="$(NM)"
DATAFLAGS += --nm-path="$(NM)"
endif
ifneq ($(OBJDUMP),objdump)
CODEFLAGS    += --objdump-path="$(OBJDUMP)"
DATAFLAGS    += --objdump-path="$(OBJDUMP)"
STRUCTSFLAGS += --objdump-path="$(OBJDUMP)"
PERFFLAGS    += --objdump-path="$(OBJDUMP)"
PERFBDFLAGS  += --objdump-path="$(OBJDUMP)"
endif
ifneq ($(PERF),perf)
PERFFLAGS += --perf-path="$(PERF)"
endif

TESTFLAGS  += -b
BENCHFLAGS += -b
# forward -j flag
TESTFLAGS  += $(filter -j%,$(MAKEFLAGS))
BENCHFLAGS += $(filter -j%,$(MAKEFLAGS))
ifdef YES_PERF
TESTFLAGS  += -p $(TEST_PERF)
BENCHFLAGS += -p $(BENCH_PERF)
endif
ifdef YES_PERFBD
TESTFLAGS += -t $(TEST_TRACE) --trace-backtrace --trace-freq=100
endif
ifndef NO_PERFBD
BENCHFLAGS += -t $(BENCH_TRACE) --trace-backtrace --trace-freq=100
endif
ifdef YES_TESTMARKS
TESTFLAGS += -o $(TEST_CSV)
endif
ifndef NO_BENCHMARKS
BENCHFLAGS += -o $(BENCH_CSV)
endif
ifdef VERBOSE
TESTFLAGS   += -v
TESTCFLAGS  += -v
BENCHFLAGS  += -v
BENCHCFLAGS += -v
endif
ifdef EXEC
TESTFLAGS  += --exec="$(EXEC)"
BENCHFLAGS += --exec="$(EXEC)"
endif
ifneq ($(GDB),gdb)
TESTFLAGS  += --gdb-path="$(GDB)"
BENCHFLAGS += --gdb-path="$(GDB)"
endif
ifneq ($(VALGRIND),valgrind)
TESTFLAGS  += --valgrind-path="$(VALGRIND)"
BENCHFLAGS += --valgrind-path="$(VALGRIND)"
endif
ifneq ($(PERF),perf)
TESTFLAGS  += --perf-path="$(PERF)"
BENCHFLAGS += --perf-path="$(PERF)"
endif

# this is a bit of a hack, but we want to make sure the BUILDDIR
# directory structure is correct before we run any commands
ifneq ($(BUILDDIR),.)
$(if $(findstring n,$(MAKEFLAGS)),, $(shell mkdir -p \
	$(addprefix $(BUILDDIR)/,$(dir \
		$(SRC) \
		$(TESTS) \
		$(TEST_SRC) \
		$(BENCHES) \
		$(BENCH_SRC)))))
endif


# commands

## Build littlefs
.PHONY: all build
all build: $(TARGET)

## Build assembly files
.PHONY: asm
asm: $(ASM)

## Find the total size
.PHONY: size
size: $(OBJ)
	$(SIZE) -t $^

## Generate a ctags file
.PHONY: tags
tags:
	$(CTAGS) --totals --c-types=+p $(shell find -H -name '*.h') $(SRC)

## Show this help text
.PHONY: help
help:
	@$(strip awk '/^## / { \
			sub(/^## /,""); \
			getline rule; \
			while (rule ~ /^(#|\.PHONY|ifdef|ifndef)/) getline rule; \
			gsub(/:.*/, "", rule); \
			printf " "" %-25s %s\n", rule, $$0 \
		}' $(MAKEFILE_LIST))

## Find the per-function code size
.PHONY: code
code: CODEFLAGS+=-S
code: $(OBJ) $(BUILDDIR)/lfs.code.csv
	./scripts/code.py $(OBJ) $(CODEFLAGS)

## Compare per-function code size
.PHONY: code-diff
code-diff: $(OBJ)
	./scripts/code.py $^ $(CODEFLAGS) -d $(BUILDDIR)/lfs.code.csv

## Find the per-function data size
.PHONY: data
data: DATAFLAGS+=-S
data: $(OBJ) $(BUILDDIR)/lfs.data.csv
	./scripts/data.py $(OBJ) $(DATAFLAGS)

## Compare per-function data size
.PHONY: data-diff
data-diff: $(OBJ)
	./scripts/data.py $^ $(DATAFLAGS) -d $(BUILDDIR)/lfs.data.csv

## Find the per-function stack usage
.PHONY: stack
stack: STACKFLAGS+=-S
stack: $(CI) $(BUILDDIR)/lfs.stack.csv
	./scripts/stack.py $(CI) $(STACKFLAGS)

## Compare per-function stack usage
.PHONY: stack-diff
stack-diff: $(CI)
	./scripts/stack.py $^ $(STACKFLAGS) -d $(BUILDDIR)/lfs.stack.csv

## Find function sizes
.PHONY: funcs
funcs: SUMMARYFLAGS+=-S
funcs: \
		$(BUILDDIR)/lfs.code.csv \
		$(BUILDDIR)/lfs.data.csv \
		$(BUILDDIR)/lfs.stack.csv
	$(strip ./scripts/summary.py $^ \
		-bfunction \
		-fcode=code_size \
		-fdata=data_size \
		-fstack=stack_limit --max=stack \
		$(SUMMARYFLAGS))

## Compare function sizes
.PHONY: funcs-diff
funcs-diff: SHELL=/bin/bash
funcs-diff: $(OBJ) $(CI)
	$(strip ./scripts/summary.py \
		<(./scripts/code.py $(OBJ) -q $(CODEFLAGS) -o-) \
		<(./scripts/data.py $(OBJ) -q $(DATAFLAGS) -o-) \
		<(./scripts/stack.py $(CI) -q $(STACKFLAGS) -o-) \
		-bfunction \
		-fcode=code_size \
		-fdata=data_size \
		-fstack=stack_limit --max=stack \
		$(SUMMARYFLAGS) -d <(./scripts/summary.py \
			$(BUILDDIR)/lfs.code.csv \
			$(BUILDDIR)/lfs.data.csv \
			$(BUILDDIR)/lfs.stack.csv \
			-q $(SUMMARYFLAGS) -o-))

## Find struct sizes
.PHONY: structs
structs: STRUCTSFLAGS+=-S
structs: $(OBJ) $(BUILDDIR)/lfs.structs.csv
	./scripts/structs.py $(OBJ) $(STRUCTSFLAGS)

## Compare struct sizes
.PHONY: structs-diff
structs-diff: $(OBJ)
	./scripts/structs.py $^ $(STRUCTSFLAGS) -d $(BUILDDIR)/lfs.structs.csv

## Find the line/branch coverage after a test run
.PHONY: cov
cov: COVFLAGS+=-s
cov: $(GCDA) $(BUILDDIR)/lfs.cov.csv
	$(strip ./scripts/cov.py $(GCDA) \
		$(patsubst %,-F%,$(SRC)) \
		$(COVFLAGS))

## Compare line/branch coverage
.PHONY: cov-diff
cov-diff: $(GCDA)
	$(strip ./scripts/cov.py $^ \
		$(patsubst %,-F%,$(SRC)) \
		$(COVFLAGS) -d $(BUILDDIR)/lfs.cov.csv)

## Find the perf results after bench run with YES_PERF
.PHONY: perf
perf: PERFFLAGS+=-S
perf: $(BENCH_PERF) $(BUILDDIR)/lfs.perf.csv
	$(strip ./scripts/perf.py $(BENCH_PERF) \
		$(patsubst %,-F%,$(SRC)) \
		$(PERFFLAGS))

## Compare perf results
.PHONY: perf-diff
perf-diff: $(BENCH_PERF)
	$(strip ./scripts/perf.py $^ \
		$(patsubst %,-F%,$(SRC)) \
		$(PERFFLAGS) -d $(BUILDDIR)/lfs.perf.csv)

## Find the perfbd results after a bench run
.PHONY: perfbd
perfbd: PERFBDFLAGS+=-S
perfbd: $(BENCH_TRACE) $(BUILDDIR)/lfs.perfbd.csv
	$(strip ./scripts/perfbd.py $(BENCH_RUNNER) $(BENCH_TRACE) \
		$(patsubst %,-F%,$(SRC)) \
		$(PERFBDFLAGS))

## Compare perfbd results
.PHONY: perfbd-diff
perfbd-diff: $(BENCH_TRACE)
	$(strip ./scripts/perfbd.py $(BENCH_RUNNER) $^ \
		$(patsubst %,-F%,$(SRC)) \
		$(PERFBDFLAGS) -d $(BUILDDIR)/lfs.perfbd.csv)

## Find a summary of compile-time sizes
.PHONY: summary sizes
summary sizes: \
		$(BUILDDIR)/lfs.code.csv \
		$(BUILDDIR)/lfs.data.csv \
		$(BUILDDIR)/lfs.stack.csv \
		$(BUILDDIR)/lfs.structs.csv
	$(strip ./scripts/summary.py $^ \
		-fcode=code_size \
		-fdata=data_size \
		-fstack=stack_limit --max=stack \
		-fstructs=struct_size \
		-Y $(SUMMARYFLAGS))

## Compare compile-time sizes
.PHONY: summary-diff sizes-diff
summary-diff sizes-diff: SHELL=/bin/bash
summary-diff sizes-diff: $(OBJ) $(CI)
	$(strip ./scripts/summary.py \
		<(./scripts/code.py $(OBJ) -q $(CODEFLAGS) -o-) \
		<(./scripts/data.py $(OBJ) -q $(DATAFLAGS) -o-) \
		<(./scripts/stack.py $(CI) -q $(STACKFLAGS) -o-) \
		<(./scripts/structs.py $(OBJ) -q $(STRUCTSFLAGS) -o-) \
		-fcode=code_size \
		-fdata=data_size \
		-fstack=stack_limit --max=stack \
		-fstructs=struct_size \
		-Y $(SUMMARYFLAGS) -d <(./scripts/summary.py \
			$(BUILDDIR)/lfs.code.csv \
			$(BUILDDIR)/lfs.data.csv \
			$(BUILDDIR)/lfs.stack.csv \
			$(BUILDDIR)/lfs.structs.csv \
			-q $(SUMMARYFLAGS) -o-))

## Build the test-runner
.PHONY: test-runner build-test
test-runner build-test: CFLAGS+=-Wno-missing-prototypes
ifndef NO_COV
test-runner build-test: CFLAGS+=--coverage
endif
ifdef YES_PERF
test-runner build-test: CFLAGS+=-fno-omit-frame-pointer
endif
ifdef YES_PERFBD
test-runner build-test: CFLAGS+=-fno-omit-frame-pointer
endif
# note we remove some binary dependent files during compilation,
# otherwise it's way to easy to end up with outdated results
test-runner build-test: $(TEST_RUNNER)
ifndef NO_COV
	rm -f $(TEST_GCDA)
endif
ifdef YES_PERF
	rm -f $(TEST_PERF)
endif
ifdef YES_PERFBD
	rm -f $(TEST_TRACE)
endif

## Run the tests, -j enables parallel tests
.PHONY: test
test: test-runner
	./scripts/test.py $(TEST_RUNNER) $(TESTFLAGS)

## List the tests
.PHONY: test-list
test-list: test-runner
	./scripts/test.py $(TEST_RUNNER) $(TESTFLAGS) -l

## Summarize the testmarks
.PHONY: testmarks
testmarks: SUMMARYFLAGS+=-spassed
testmarks: $(TEST_CSV) $(BUILDDIR)/lfs.test.csv
	$(strip ./scripts/summary.py $(TEST_CSV) \
		-bsuite \
		-fpassed=test_passed \
		$(SUMMARYFLAGS))

## Compare testmarks against a previous run
.PHONY: testmarks-diff
testmarks-diff: $(TEST_CSV)
	$(strip ./scripts/summary.py $^ \
		-bsuite \
		-fpassed=test_passed \
		$(SUMMARYFLAGS) -d $(BUILDDIR)/lfs.test.csv)

## Build the bench-runner
.PHONY: bench-runner build-bench
bench-runner build-bench: CFLAGS+=-Wno-missing-prototypes
ifdef YES_COV
bench-runner build-bench: CFLAGS+=--coverage
endif
ifdef YES_PERF
bench-runner build-bench: CFLAGS+=-fno-omit-frame-pointer
endif
ifndef NO_PERFBD
bench-runner build-bench: CFLAGS+=-fno-omit-frame-pointer
endif
# note we remove some binary dependent files during compilation,
# otherwise it's way to easy to end up with outdated results
bench-runner build-bench: $(BENCH_RUNNER)
ifdef YES_COV 
	rm -f $(BENCH_GCDA)
endif
ifdef YES_PERF
	rm -f $(BENCH_PERF)
endif
ifndef NO_PERFBD
	rm -f $(BENCH_TRACE)
endif

## Run the benchmarks, -j enables parallel benchmarks
.PHONY: bench
bench: bench-runner
	./scripts/bench.py $(BENCH_RUNNER) $(BENCHFLAGS)

## List the benchmarks
.PHONY: bench-list
bench-list: bench-runner
	./scripts/bench.py $(BENCH_RUNNER) $(BENCHFLAGS) -l

## Summarize the benchmarks
.PHONY: benchmarks
benchmarks: SUMMARYFLAGS+=-Serased -Sproged -Sreaded
benchmarks: $(BENCH_CSV) $(BUILDDIR)/lfs.bench.csv
	$(strip ./scripts/summary.py $(BENCH_CSV) \
		-bsuite \
		-freaded=bench_readed \
		-fproged=bench_proged \
		-ferased=bench_erased \
		$(SUMMARYFLAGS))

## Compare benchmarks against a previous run
.PHONY: benchmarks-diff
benchmarks-diff: $(BENCH_CSV)
	$(strip ./scripts/summary.py $^ \
		-bsuite \
		-freaded=bench_readed \
		-fproged=bench_proged \
		-ferased=bench_erased \
		$(SUMMARYFLAGS) -d $(BUILDDIR)/lfs.bench.csv)


# rules
-include $(DEP)
-include $(TEST_DEP)
-include $(BENCH_DEP)
.SUFFIXES:
.SECONDARY:

$(BUILDDIR)/lfs: $(OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

$(BUILDDIR)/liblfs.a: $(OBJ)
	$(AR) rcs $@ $^

$(BUILDDIR)/lfs.code.csv: $(OBJ)
	./scripts/code.py $^ -q $(CODEFLAGS) -o $@

$(BUILDDIR)/lfs.data.csv: $(OBJ)
	./scripts/data.py $^ -q $(DATAFLAGS) -o $@

$(BUILDDIR)/lfs.stack.csv: $(CI)
	./scripts/stack.py $^ -q $(STACKFLAGS) -o $@

$(BUILDDIR)/lfs.structs.csv: $(OBJ)
	./scripts/structs.py $^ -q $(STRUCTSFLAGS) -o $@

$(BUILDDIR)/lfs.cov.csv: $(GCDA)
	$(strip ./scripts/cov.py $^ \
		$(patsubst %,-F%,$(SRC)) \
		-q $(COVFLAGS) -o $@)

$(BUILDDIR)/lfs.perf.csv: $(BENCH_PERF)
	$(strip ./scripts/perf.py $^ \
		$(patsubst %,-F%,$(SRC)) \
		-q $(PERFFLAGS) -o $@)

$(BUILDDIR)/lfs.perfbd.csv: $(BENCH_TRACE)
	$(strip ./scripts/perfbd.py $(BENCH_RUNNER) $^ \
		$(patsubst %,-F%,$(SRC)) \
		-q $(PERFBDFLAGS) -o $@)

$(BUILDDIR)/lfs.test.csv: $(TEST_CSV)
	cp $^ $@

$(BUILDDIR)/lfs.bench.csv: $(BENCH_CSV)
	cp $^ $@

$(BUILDDIR)/runners/test_runner: $(TEST_OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

$(BUILDDIR)/runners/bench_runner: $(BENCH_OBJ)
	$(CC) $(CFLAGS) $^ $(LFLAGS) -o $@

# our main build rule generates .o, .d, and .ci files, the latter
# used for stack analysis
$(BUILDDIR)/%.o $(BUILDDIR)/%.ci: %.c
	$(CC) -c -MMD $(CFLAGS) $< -o $(BUILDDIR)/$*.o

$(BUILDDIR)/%.o $(BUILDDIR)/%.ci: $(BUILDDIR)/%.c
	$(CC) -c -MMD $(CFLAGS) $< -o $(BUILDDIR)/$*.o

$(BUILDDIR)/%.s: %.c
	$(CC) -S $(CFLAGS) $< -o $@

$(BUILDDIR)/%.c: %.a.c
	./scripts/prettyasserts.py -p LFS_ASSERT $< -o $@

$(BUILDDIR)/%.c: $(BUILDDIR)/%.a.c
	./scripts/prettyasserts.py -p LFS_ASSERT $< -o $@

$(BUILDDIR)/%.t.a.c: %.toml
	./scripts/test.py -c $< $(TESTCFLAGS) -o $@

$(BUILDDIR)/%.t.a.c: %.c $(TESTS)
	./scripts/test.py -c $(TESTS) -s $< $(TESTCFLAGS) -o $@

$(BUILDDIR)/%.b.a.c: %.toml
	./scripts/bench.py -c $< $(BENCHCFLAGS) -o $@

$(BUILDDIR)/%.b.a.c: %.c $(BENCHES)
	./scripts/bench.py -c $(BENCHES) -s $< $(BENCHCFLAGS) -o $@

## Clean everything
.PHONY: clean
clean:
	rm -f $(BUILDDIR)/lfs
	rm -f $(BUILDDIR)/liblfs.a
	rm -f $(BUILDDIR)/lfs.code.csv
	rm -f $(BUILDDIR)/lfs.data.csv
	rm -f $(BUILDDIR)/lfs.stack.csv
	rm -f $(BUILDDIR)/lfs.structs.csv
	rm -f $(BUILDDIR)/lfs.cov.csv
	rm -f $(BUILDDIR)/lfs.perf.csv
	rm -f $(BUILDDIR)/lfs.perfbd.csv
	rm -f $(BUILDDIR)/lfs.test.csv
	rm -f $(BUILDDIR)/lfs.bench.csv
	rm -f $(OBJ)
	rm -f $(DEP)
	rm -f $(ASM)
	rm -f $(CI)
	rm -f $(TEST_RUNNER)
	rm -f $(TEST_A)
	rm -f $(TEST_C)
	rm -f $(TEST_OBJ)
	rm -f $(TEST_DEP)
	rm -f $(TEST_CI)
	rm -f $(TEST_GCNO)
	rm -f $(TEST_GCDA)
	rm -f $(TEST_PERF)
	rm -f $(TEST_TRACE)
	rm -f $(TEST_CSV)
	rm -f $(BENCH_RUNNER)
	rm -f $(BENCH_A)
	rm -f $(BENCH_C)
	rm -f $(BENCH_OBJ)
	rm -f $(BENCH_DEP)
	rm -f $(BENCH_CI)
	rm -f $(BENCH_GCNO)
	rm -f $(BENCH_GCDA)
	rm -f $(BENCH_PERF)
	rm -f $(BENCH_TRACE)
	rm -f $(BENCH_CSV)